Acquired multiple pilosebaceous cysts on the face having the histopathological features of steatocystoma multiplex and eruptive vellus hair cysts.

摘要

A 59-year-old Japanese woman had a persistent skin eruption located on the face for 5 years' duration. These asymptomatic yellowish papules had gradually increased in number. She had approximately 30 lesions, 1-3 mm in diameter, with a smooth surface. No other area of the body had a similar eruption. There was no other relevant family history of similar lesions. No tendency to remission was observed.Histopathology of the lesion excised from her right cheek showed a cyst in the mid-dermis that was lined by 3-4 cell layers of undulating squamous epithelium. Crenulated, homogenous and eosinophilic cuticle lined the keratinous cyst. An overlying epidermis was normal. The cyst was filled with amorphous, laminated keratinous material and numerous vellus hair shafts. A sebaceous gland was attached to the deepest part of the cyst wall. A telogen hair follicle was not connected to the cyst wall. The cyst was diagnosed as a facial papular variant of steatocystoma multiplex (SM) with overlapping features of eruptive vellus hair cysts (EVHCs).